Launcher

The launcher is the desktop face of PoZoUSEMS: it finds your Steam games, lists installed mods, and launches the injected game with one click.

Running it

cargo build -p usems-launcher
target\debug\usems-launcher.exe

The window shows:

• Header — version + detection status
• Right panel — re-detect button, injection-delay slider, LAUNCH
• Center — every mod under <game>/mods/ with enable checkboxes
• Bottom — rolling activity log

Game detection

Detection scans every Steam library for the game’s appmanifest_<appid>.acf and verifies the executable actually exists inside installdir. Sources probed, in order:

1. STEAM_PATH environment variable (override for portable installs)
2. C:\Program Files (x86)\Steam
3. HKCU\Software\Valve\Steam\SteamPath registry value
4. Every additional library from that install’s libraryfolders.vdf

Game	AppID	Status
Portal 1	400	detected + launch-verified
more titles	—	as caps land per title

First successful detection is persisted to %APPDATA%\PoZoUSEMS\launcher.toml:

game_dir = 'D:\!stem\steamapps\common\Portal'
inject_delay_ms = 12000

Mod management

The mod list reads <game>/mods/*/mod.toml directly (same discovery rules as the core). The checkbox writes only the enabled = true/false line in the package’s manifest, preserving all other content byte-for-byte — comments survive. Unticked mods are skipped by the loader at next launch.

LAUNCH

One click spawns the sibling usems-injector.exe with everything wired:

usems-injector --exe <game>\hl2.exe
               --args "-game portal -steam -novid -console"
               --dll  <x86 usems_core.dll>
               --delay 12000 --timeout 5000

Resolution order for both helper binaries: same directory as the launcher, then the cargo workspace target\... layouts (debug, then release). The core DLL must be the x86 build (i686-pc-windows-msvc) since Portal is a 32-bit process.

The injection delay slider exists because the engine needs time to map its DLLs before the core can arm (see Injection Pipeline timing table).

Roadmap (rest of Phase 5)

• profiles: named enable/disable sets per game
• mod browser: install-from-folder, delete packages
• inject status feedback (watch injector exit code; tail core log)
• release build bundling: launcher + injector + core in one zip